Bitcoin gets new friends, but still a bit player

Bitcoin scored several big wins this week, including endorsements from U.S. federal officials and Virgin Group founder Richard Branson, signalling its progress toward wider acceptance.

It's a wonder Bitcoin is still around at all, after a series of shutdowns of exchanges, account seizures and massive selloffs. Tokyo-based Mt. Gox, one of the largest exchanges, temporarily shut down in April after a huge drop in the currency's price.

Some groups have still not gotten back on their feet. Tradehill, another large Bitcoin exchange, said in August that it would be suspending its trading, citing banking and regulatory issues. Trading has not been resumed, judging by its website.

Still, the number of stores accepting the virtual currency continues to rise. Bitpay, which provides a service that makes it easier for merchants to get paid in bitcoins, says it's now used by 12,000 merchants worldwide.